Multiple lift truck



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A. M. BARRETT MULTIPLE LIFT TRUCK Filed Feb. 26, 1930 4 'Sheets-Sheet 2ITufenr ifm s April 17, 1934.

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A. M. BARRETT 1,954,986 MULTIPLE LIFT TRUCK Filed Feb. 25, 1930 4Sheets-Sheet 4 jg@ f @sa Patented Apr. 17, 1934 intrest MULTIPLE IFTTRUCK Arthur M. Barrett, Winnetka, Ill., assigner to Barrett-CravensCompany, Chicago, Ill., a corporation of Illinois Application February26, 1930, Serial No. 431,436

24 Claims.

lvy invention relates to lift trucks of the type comprising a mainsupporting frame carried upon wheels and arranged to be steered by meansof a steering hanme which also serves as a means for operating mechanismfor raising a lifting frame or platform Inova-bly supported on the mainframe. When the lifting frame or platform is in its lowered position thetruck is adapted to be backed under a platform upon which the load to'be transported has been placed, and then by operating the steeringhandle from any steering position the platform and load thereon israised from the floor so that the load can be easily transported fromone place to another.

i My invention has to do with improved means for raising the liftingframe and for controlling the lowering thereof, and with improved meansfor mounting the lifting mechanism on the main frame. My invention alsohas to do with imfi proved means for supporting the lifting frame on thesupporting frame and with improved means for retaining the lifting frameor platform in any of its raised positions. Still further, my presentinvention has to do with improved means for releasing the retainingmeans and the lifting means so as to allow the lifting frame and anyload that may be thereon to lower. i

Other objects and advantages of my present invention will be apparent tothose skilled in the of the following detailed description of oneembodiment of the same, together with the accompanying drawingsillustrating such embodiment and in which:

Figure 1 is a top or plan View of the preferred form of my invention;

Figure 2 is a fragmentary sectional View, on an enlarged scale, takensubstantially on the line 2--2 of Figure 1;

1) Figure S is a sectional View, on an enlarged scale, taken on the line3 3 of Figure 1;

Figure 4 is a View partly in section and partly in elevation and showingon an enlarged scale a portion of the manually operated releasing 3means for throwing the lifting pawls and the retaining pawl out ofoperative engagement;

Figure 5 is a side elevation on the same scale as Figure l and showingsome parts broken away to better disclose some of the lifting mechanismand the supporting means for the lifting frame;

Figure 6 is an enlarged detail view on the line 6-6 of Figure 3 showingone of the links connecting the steering handle with the liftingmechanism, which link is oscillatable with respect to 3 Vthe liftingmechanism;

art to which it appertains after a consideration Figure 'Z is a crosssection lookingrearwardly and taken on the line 7-7 of Figure 1; l

Figure 8 is a section taken on the line 8-8 of Figure 1; and

Figure 9 is an enlarged section taken substantially on the line 9---9lof Figure 1.

Referring now to the drawings, the main or supporting frame 1 is seen tocomprise side bars 2 and 3 connected together at their front ends by acrosshead 4. The rearward ends of the side bars 2 and 3 are each bentdownward, as at 6 and 7, and are apertured to receive the lower rearaxle 8. As best shown in Figures 1 and 5, the side bars 2 and 3 areconnected to the crosshead 4 by means of bolts 10 and 11. each of theside bars 2 and 3 and the crosshead 4 and pivoted on the bolts l0 is apair of front links 12 whose purpose will be described later.

The other bolts l1 securing the front ends of the bars 2 and 3 includeappropriate spacing r means (not shown) to space the side bars from thecrosshead 4 a distance corresponding to the thickness of the front links12 pivoted on the bolts 10.

The crosshead 4 is seen to comprise a front portion upwardly arched, asat 15, and which is provided with an intermediate enlarged section whichisrformed to provide bearing bosses 17 and' 18 affording a verticaljournal for the front king bolt 20. At its lower end the king bolt 20 isprovided with a fiange 21 which serves as a seat for the roller bearingassembly 23. At the lower end of the king bolt 20 and below the flange21 there is provided a pair of forked extensions 25 which are joined bya horizontal web 26 at their" lower ends and which are apertured toreceive the front axle 27. Journaled on the front axle 27 is a pair offront steering wheels 28.

Between Secured to the top of the king bolt 20, as by a clamping bolt30, is a cap 32 which is provided with a ange 33 bearing against the topof the `bearing boss 18 and which serves to hold the king bolt 20 in thecrosshead 4. Extending forwardly and upwardly of the king bolt cap 32 isa pair of apertured ears 35 adapted to receive the pivot bolt 37therethrough. 5

The pivot bolt 37 defines the horizontal axis about which the steeringhandle has vertical swinging movement and which is thereby pive o'tallysecured to the cap 32. Since the king bolt 2) and the cap 32 securedthereto is rotatable about a vertical axis it is obvious that thesteering handle 4.0 can be turned laterally to` position the steeringwheels 28' for the purpose of guiding the truck. The handle 40 may alsobe provided with a handle grip (not shown) at its outer end and whichserves as a convenient means for pulling the truck from place to place.

The lower rear axle 8 at the rear ends of the side bars 2 and 3 carriesin the usual manner the supporting wheels e4.

The upper lifting frame or platform comprises the substantially U-shapedmember 50, preferably formed from a metal bar of suitable dimensions,and the forward ends of the U-shaped member are connected to the frontlinks 12 by means of bolts 51 or the equivalent. Near the rear end ofthe upper lifting frame or platform 50 there is provided a transverseangle member 52 welded or otherwise secured thereto and so arrangedtherein that the flanges of the angle member 52 extend forwardly anddownwardly respectively.

Rear links 54 are secured to the axle 8 at their lower ends and to atransversely bearing member 55 at their upper ends. As clearly shown inFigures 1 and 5 the bearing member 55 is received in the angle of themember 52 in such a manner that the bearing member 55 has supportingcontact throughout substantially its entire length, thus providing awide bearing .for supporting the rear end of the upper lifting frame orplatform 50. This supporting bearing structure is further strengthenedby means of struts 56 which are clamped, as by bolts 57, to the lowerrear axle 8, these struts 56 also being secured to the transverselyextending bearing member 55 as by welding. From Figure l it will benoted that the supporting wheels 44 are positioned between one of therear links 54 and one of the struts 56. This provides a. very strong andsturdy rear axle construction and makes for a long lived truck.

The platform 50 adapted to be raised and lowered with respect to themain supporting frame l, and it will be noted from Figure 5 that thefront links 12 and the rear links 54 extend diagonally upwardly andrearwardly of the main frame l and in substantial parallelism with `oneanother. If, for example, the platform 50 were moved longitudinallyforward from the position where it rests Yupon the main supporting frame1 as shown in Figure 5 the platform 50 would also be elevated withrespect to the main frame 1 by virtue of the links 12 and 54 swingingforwardly and upwardly a counter-clockwise direction as shown in Figure5.`

, My present invention contemplates the provision of an improved meansfor effecting such lifting movement, and such improved means will now bedescribed.

A pair of Shaft bearing brackets 60 is bolted to the lower supportingframe, which bearing brackets provide journals' for rotatably supporting the main shaft 61, see Figure 1. A lifting crank 63 is keyed orotherwise secured to either end of the main shaft 61 and in a positiontolie closely adjacent to the side `bars 2 and 3 and the I forwardlyextending bars of the Ushaped upper lifting frame or platform 56. Eachof the cranks 63 is connected to the platform by an upwardly andforwardly extending lifting link 65, the lifting link 65 being connectedto the crank 63 by means of a lifting crank pin 66 and to the platform50 by means of a bolt 68.

The main shaft 61 is adapted to be rotated by a lifting ratchet 76 keyedthereto as indicated in Figure 3. Journaled on the main shaft 61 andembracing the lifting ratchet 70 is a pair of lifting arms or levers 71connected to operate together by means of connecting shafts 72 and 73,the latter of which may be termed a lifting pawl shaft since there ismounted thereon a pair of pawls 75 which are journaled thereon andadapted to engage the teeth 76 formed on the lifting ratchet 70. Each ofthe pawls 75 is weighted, as at 78, so as to be continually biasedtoward engagement with the teeth 76 on the ratchet member 70.

kEach of the pawls 75 is also provided with an inwardly extending lug 79for a purpose to be later described.

The forward ends of the lifting arms or levers are connected together bythe shaft 72, as indicated in Figures 3 and 6. My present inventioncontemplates connecting the lifting levers 7l to the vertically swinginghandle member ll0 so that when the handle 40 is oscillated up and downthe lifting levers are adapted to cause the ratchet 70 to turn the shaft61 and the cranks 63 connected therewith so as to exert a force throughthe lifting links 65 to move the lifting platform 50 forwardly andupwardly with respect to the main supporting frame l. The connectingmeans between the handle 40 and the lifting arms or levers 71 is seen tocomprise a series of connected elements one of which is the double link86 having a hook 8l at its lower end which has engagement with theconnecting shaft 72. The double link 80 is held on the shaft 72 by thebolt 82. As is shown in Figure 6, the hook 81 is so formed that thedouble link 80 is capable of swinging laterally with respect to thelifting arms or levers 71. The upper end of the double link 80 isprovided with an eye 83 which receives the lifting lever 85. The liftinglever 85 is provided with a lower curved portion 86 adapted 'to operatewithin the eye 83 of the double link 8G. The lifting lever 85 is pivotedto the king bolt cap 32`by the pivot bolt 37 which also pivotallysecures the handle 40 to the outstanding ears 35 provided on the cap 32,see Figure 3.

The upper end of the lifting lever 85 is formed with a bend 87 adaptedto be latched to the handle 40 so that vertical oscillations of thehandle 40 may beV communicated to the lifting lever 85. When the latter'is thus oscillated the double link 80 exerts a lifting force on 'thelifting arms or levers 7l which, in turn, is transmitted through theshaft 6l and the cranks 63 to the lifting links 65 and lateral movementwhich the double link 86 is capable of, relative to the lifting levers71, the handle 40 can be actuated to operate the lifting mechanism inany normal steering position.

That is, the handle 40 need not be brought into t longitudinal alignmentwith the truck before the platform 56 can be elevated, as is necessaryin some trucks in use at present, but the handle may be turned through180 or more when steering the truck, and in any position within this lrange it is operative to lift the platform.

The lifting frame or platform 56 is held in any of its elevatedpositions by a pawl and ratchet mechanism connected to operate betweenthe lifting ratchet 70 and the lower main frame l, Referring to Figures2 and 3 it will be noted that the lifting ratchet 70 is provided with apair of rearwardly extending ears 96 having apertures to receive a hinge91. A check hinge 62 is pivotally mounted on the the ears 90, andflxedly secured to the check hinge, as by welding, is the tube orcylinder 93. Threadedly secured to the cylinder 93 is the auxiliarychamber 94 for holding a supply of oil therein and having at itsrearward end an the platform 50. By virtue of the J, lli

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hinge pin 91 between apertured boss 96 through which passes theV pistonrod 98. The chamber 94 is held xed to the cylinder 93 by the lock nut95. A piston structure 99, including a valve disc 100 slidable on thereduced end 98 ofthe piston rod 98 and a valve 101 xed to the piston rod98, is carried at the forward end of the piston rod 98 and operates inthe cylinder 93. The forward portion of the piston rod 98 is providedwith screw threads having a steep pitch `and which are operativelyassociated with a screw nut 102 securely held between the cylinder 93and the chamber 94. The nut 102 is prevented from turning relative tothe cylinder 93 by being formed with a slot or recess' 103 in which isreceived the tongue or projection 104 formed on the cylinder 93.

It will therefore be seen that relative longitudinal movement betweenthe cylinder and chamber structure and the piston rod 98 will occasion arotary movement of the latter.

The rear end of the piston rod 98 is mounted' in a bearing which allowsfor both rotary movement of the piston rod 98 and also swinging movementthereon, which bearing is seen to comprise the bearing mounting 105securely bolted or otherwise fixed to a transverse angle member 106mounted on lower main frame 1 between the side bars 2 and 3. n additionto the bearing mounting 105, the bearing referred to above also includesthe bearing. adapter 107 secured to the end 108 of the piston rod 98 bymeans of a pair of nuts 110 threaded onto lthe piston rod 98. Betweenthe adapter 107 and the mounting 105 is an inner ring 109er, an outerring 1095 and an assembly of antifriction rolls 114 so formed andarranged that the piston rod 98 is capable of a limited amount o f upand down swinging while, at the same time, being rotatably mounted inthe bearing mounting 105 on the supporting frame 1.

A bearing mounting cap 112 is secured to the bearing mounting 105 bymeans of four bolts 113,

Vand the cap 112 is provided interiorly with thrust bearings 115cooperating with the forward surface of the adapter 107 to maintain thepiston rod 98 in proper position relative to the bearings 114.

The forward portion of thecap 112 is formed to be spherical about thevirtual point of up and down swinging of thepiston rod 98 and isarranged to cooperate with the similarly formed extension 117 providedon the check ratchet 120.

The spherical portion of the extension 117 is provided with a number ofoil retaining grooves 118.

Referring now to Figures 1 and 7, it will be observed that the bearingmounting 105 is provided with a lateral extension 125 havingV a pair offorwardly extending apertured ears 126 and a boss 127 which provides asupport for the forwardly extending pin 128 secured therein. Mounted onthe pin 128 and extending adjacent to the ears 126 is the check pawl 130having a weighted extension 131 so that the pawl 130`is urged towardengaging position with the check ratchet 120 mounted on the piston rod98 to turn therewith. A set screw 132 serves to secure the check ratchet120 to the piston rod 98. The check ratchet 120 may also be keyed to thepiston rod 98, as by a key 133.

The operation of the machine as thus far described is as follows. Whenthe lifting lever 85 islatched to the handle 40, the latch 135 beingpivoted on the handle for that purpose, one downward sweep of the handlewill raise the double linl; 80 which, in turn, will rock theliftingarmsf 71 about their axis on the shaft 61 and, through thelifting pawls 75, turn `the lifting ratchet in a clockwise direction asviewed in Figure 3.

This will cause the cranks 63 to be turned in the same direction and toexert a forward and upward force through the lifting links to theplatform 50 to elevate the same a certain amount. The clockwise rotationof the lifting ratchet will, however, move the check tube 93 and chamber94 forward with respect to the piston rod 98, the latter being held fromforward movement by the thrust bearing` 115 and the cap 112. The forwardmovement of the mainV screw nut 102 along the piston rod 98 will causethe latter to turn carrying with it the check; ratchet 120, turning thelatter in a counter-clockwise direction as viewed in Figure 7. When thelifting frame 50 is thus elevated above its lowermost position the checkpawl 130 will prevent the clockwise rotation of the check ratchet 120and thus hold the platform 50 in its raised position. The handle 40 isthen raised which allows the double link. to move downwardly carryingwith it the lifting arms or levers 71, the lifting pawls 75 movingfreely over the teeth 76 of the lifting ratchet 70.

The handle 40 may then be given another downward movement whereupon thelifting pawls 75 will engage with the lifting ratchet 70 to rock theshaft 61 and raise the platform 50 to another position. Further forwardmovement of the nut 102 along the piston rod 98 will occasion a furtherrotation of the check ratchet 120 so that when the handle 40 is broughtto its lowered position the second time the check pawl 130 again engagesand holds the check ratchet 120 from returning.

The relation between the number of teeth on the lifting and holdingratchets and the pitch of threadson the piston rod 98 is such that for amovement of the lifting arms through a distance of one tooth of thelifting ratchet the check ratchet is rotated through a distance equal toseveral teeth thereon, whereby the lifting platform is held in positionsintermediate the positions to which it is raised by an advance equal toone tooth on the lifting ratchet.

4Thus it will be clear that the handle 40 may be oscillated up and downany number of times that it is necessary to elevate the platform 50 andthe load thereon to its maximum raised position, the check pawl andassociated structure effectively holding the platform 50 and load at anyof its raised positions.

When the load has been raised and the truck transported to the desiredposition it then becomes necessary to release the means holding theplatform 50 in its elevated position and I will now describe theimproved means I have provided to secure this result. 1t must beremembered that in order to allow the load to lower it is necessary notonly to release the holding pawl'130 but also the lifting pawls 75. Thecrosshead 4 is provided with a pair of rearwardly extending aperturedears carrying a pin 141 held therein by means of cotter keys 142, andthe pin 141 provides a pivotal support for afoot treadle 144 havingthree arms.

One ofthe arms, 145, extends forwardly for'convenient operation by thefoot of the operator in releasing the pawls to allow the load to lower,an-

other of the arms, 146, extendsrearwardly and is "f adapted to bepressed by the foot of the operator when it is desired to return thelifting pawls and the retaining pawls to their operative positions,

andthe third arm, 147, extends downwardly and is connected by means ofthe 1ink'150v to a pawlzrelease cam lever 151 which is pinned to theshort shaft 153, see Figure 4.

This shaft 153 is journaled in a pawl release cam bearing 154 supportedon the main shaft 61. 'Ihe pawl release cam bearing 154 is, however,held from rotation with the main shaft 61 by the cam bearing brace 155which is bolted to the lower portion of the pawl release cam bearing 154and extends upwardly and forwardly for connection through the crosshead4 at 156. Secured to the inner end of the shaft 153 is the pawl releasecani 169, and which is arranged to move thereagainst and raise the pawlrelease arm 161 which is Xedly secured to the pawl stripper shaft 73rotatable in the lifting arms 71. Collars 163 are pinned or otherwisesecured to either end of the shaft '73, as shown in Figure 9. Secured tothe shaft '78, as by welding or the like, is the pawl stripper 165, andas shown in Figure 9, the pawl stripper 165 is mounted between thelifting pawls 75 and extends upwardly from the shaft 73 to a positionfor operative engagement with the lugs 79.

Referring now to Figure 4, it will be obvious that when the treadle 144is operated by stepping on the arm 145 to depress the same the link 159will be urged to the right in Figure 4 to rock the pawl release camlever 151 in a clockwise direction which, through the short shaft 153,rotates the pawl release cam 160 in the same direction.

This rotation of the cam 160 causes the same to move up into engagementwith the pawl release arm 161 and to rock the same and the shaft 73connected therewith in a counter-clockwise direction. Such rotation ofthe shaft 73 will carry with it the pawl stripper 165, see Figure 3,which will bear against the lugs '79 to move the lifting pawls out ofengagement with the teeth 76 of the lifting ratchet 79. Thus the liftingratchet 70 will be free to turn in a counter-clockwise direction asviewed in Figure 3 to allow the platform to lower.

The platform 50 will not lower however until the check pawl 130 isreleased from engagement with the check ratchet 126. As will be seenfrom Figures 1, 4 and 7, a link 170 extends rearwardly from the point ofconnection of the link 150 with the pawl release cam lever 151, see alsoFigure 8, and is connected at its rearward end with the check pawlstripper 171 at the lower end thereof. The check pawl stripper 171 isprovided with an upper forwardly extending finger 172 adapted to contactwith the abutment 173 formed on the check pawl 139 as shown in Figure 7.The check pawl stripper 171 is pivotally mounted between the ears 126.It is thus evident that whenever the foot treadle arm 145 is depressedto release the lifting pawls 75 the link 170 is moved rearwardly to rockthe check pawl stripper 171 to cause the saine to depress the abutment1'73 and move the check pawl 130 out of engagement with the checkratchet 120.

Thus the platform 50 and any load thereon will move downwardly under theaction of gravity.

Under most conditions it is desirable to provide some means forcushioning the return of the load and platform 50 to its loweredposition. Referring now to Figure 2 it will be clear that when theplatform 59 moves downwardly the ,lifting ratchet 79, see Figure 3, willbe rotated in a counter-clockwise direction and thus cause the checktube 93 and chamber 94 to move to the right as viewed in Figure 2. Thusthe piston 99 will be moved, that is relative to the check tube orcylinder 93, toward the closed end of the cylinder 93. I propose to llthe cylinder 93 with lubricating oil or other fluid of suitablecharacteristics and to provide a restricted passage for the oil so thatwhen the piston 99 moves toward the closed end of the cylinder 93considerable resistance will be encountered due to the friction of theoil flowing through the restricted passage from in front of the piston99. In order, however, that such resistance will not be encountered inlifting the platform 50 I provide for removing the restriction to theflow of oil when the platform is raised. Referring to Figure 2 it willbe noted that there is a limited amount of movement of the valve disc100 along the reduced end 98 of the piston rod 98, soy that when thecylinder 93 is drawn to the left in Figure 2, the disc 100 is moved awayfrom the valve 101, which is smaller than the cylinder 93, so that theoil may flow freely around between the valve 191 and the disc 100 andthen through the clearance 100 between the disc 100 and the end 98 ofthe piston rod 98 to fill the space to the left of the piston 99 inFigure 2. When, however, the cylinder 93 is moved to the right, as whenthe platform 59 lowers, the disc 100 is moved against the valve 101 sothat now the oil must flow through the restricted opening 101' in thevalve 101, thus effectively cushioning the return of the platform.

A passage 175 is provided in the main screw nut 192 andV is for thepurpose of affording communication between the rearward end of thecylinder 93 and the auxiliary chamber 94 so that oil from the latter mayflow into the cylinder 93. In conjunction with the boss 96 formed at therearward end of the chamber 94 I provide a gland 190 and a packing 181surrounding the piston rod 98 so that the chamber 94 is substantiallyleakproof. I also provide a spring 182 biased between the main screw nut192 and the gland 189 for the purpose of continually urging the latteragainst the packing 181 to force the same against the piston rod 98.

Attention is directed to Figures 4 and 5 wherein will be noted that thepawl release arm 161 is of such a length that the pawl release cam maybe moved to a position substantially at right angles to the cam surfaceof said release arm, this being for the purpose of allowing the foottreadle 144 and pawl releasing mechanism associated therewith to remainin pawl releasing position. When it is desired to return the pawls toholding position the arm 146 is depressed by the foot of the operator torock the foot treadle 144 in a clockwise direction as shown in Figure 4to thereby return the pawl release cam 160 from holding position to theposition indicated in Figure 4. rThis movement will also allow the checkpawl 130 to return to the position shown in Figure 7.

In handling heavy loads the retaining mechanisin and the cushioningmeans is subjected to considerable strain, and I propose to strengthenthe angle member 106 by the use of diagonal braces 109 and side plates111 all securely welded or otherwise rigidly fastened together and whichmay be bolted to the side bars 2 and 3 by the means of bolts 116.

When it is necessary to allow the platform 50 to return to loweredposition without load the resistance encounteredr by virtue of thecushioning means is usually great enough to prevent the speedy return ofthe lifting frame or platform 50.

In order to hasten the return when there is no load on the truck Iprovide a pair of springs 185 acting between the transverse angle member106 on the main or supporting frame 1 and brackets 186 on the liftingframe 50 as shown in Figure 1, to move the latter rearwardly and thusaid to swing the same on the links 12 and 54 to its lowered position.Thus when the platform 50 is raised the springs 185 are placed undertension and which when the pawls are released aid in lowering theplatform. The springs 185 may be secured to the angle member 106 and thebrackets 186 by having ends passed through holes therein.

While I have described, in connection with the accompanying drawings,the specific form in which I prefer to embody my invention, it is to beunderstood that the invention is not to be limited to the specific meanswhich I have herein shown and described, and that, in fact, widelydifferent means may be employed in the practice of the broader aspectsof my invention.

What I claim, therefore, and desire to secure by Letters Patent is:

l. A lift truck comprising the combination of wheeled supporting means,a lifting frame, means for raising the lifting frame, and means forretaining the lifting frame in any raised position including a ratchetmounted on the wheeled supporting means for both pivotal and rotationalmovement.

2. A lift truck comprising the combination of supporting means, aplatform elevatable with respect thereto, means for lifting the platformcomprising a shaft journaled on the supporting means, a ratchet securedthereto, a manually operated lever, a lifting lever mounted on saidshaft and having pawl means to actuate the ratchet, means comprising aseries of links having limited lateral movement and adapted tooperatively connect the two levers, and releasable means to retain theplatform in elevated position.

3. A lift truck comprising the combination of supporting means, aplatform elevatable with respect thereto, means for lifting the platformcomprising a shaft journaled on the supporting means, a ratchet securedthereto, a manually operated lever, a pair of lifting levers journaledon said shaft and having pawl means to actuate the ratchet, said leversextending outwardly beyond said pawl means, means connecting theoutwardly extended ends of said pair of lifting levers, and meansadapted to connect the aforesaid means joining said extended ends of thelifting levers with said manually operated lever, said last means beingcarried by the manually operated lever and the lifting levers.

4. A lift truck comprising a supporting frame and a lifting platform, aplurality of swinging links supporting the platform on the frame, ashaft journaled on the frame, cranks on the shaft, links connecting thecranks with the platform, means to rotate the shaft, including a ratchetsecured to the shaft, a lifting lever journaled to turn about the shaft,a ratchet engaging pawl on said lever, means to oscillate the liftinglever to raise the platform, and manually operative means to releasesaid pawl to allow the platform to lower, said last named meansincluding a member journaled on said shaft.

5. A lift truck comprising a supportingfframe and a lifting platform, aplurality of swinging links supporting the platform on the frame, a

shaft journaled on the frame, cranks on the shaft,

links connecting the cranks with the platform, means to rotate theshaft, including a ratchet secured to the shaft, a lifting leverjournaled to turn about the shaft, a ratchet engaging pawl on saidlever, means to oscillate the lifting lever to raise the platform, andmanually operative means to release said pawl to allow the platform tolower, said last named means including a member journaled on said shaft,a pawl stripper pivoted on said member, and means to hold said memberfrom turning with the shaft.

6. A lift truck comprising a supporting frame and a lifting platform, aplurality of swinging links supporting the platform on the frame, ashaft journaled cn the frame, cranks on the shaft, links connecting thecranks with the platform, means to rotate the shaft, including a ratchetsecured to the shaft, a lifting lever journalcd to turn about the shaft,a ratchet engaging pawl on said lever, means to oscillate the liftinglever to raise the platform, pawl and ratchet means to retain theplatform in elevated position, and means to release the pawls of thelifting means and the retaining means to allow the platform to lower,said means comprising a foot treadle mounted on the supporting frame, amember journaled on said shaft and having a pawl stripper pivotedthereto in operative relation with the pawl of the lifting means, meansincluding a link connecting said foot treadle and said pawl stripper,and means including a second link connected with the first link torelease the pawl of the retaining means whenever the foot treadle isoperated to actuate the pawl stripper. l

A lift truck comprising a supporting frame and a lifting platform, aplurality of swinging links supporting the platform on the frame, ashaft journaled on the frame, cranks on the shaft, links connecting thecranks with the platform, means to rotate the shaft, including a ratchetsecured to the shaft, a lifting lever journaled to turn about the shaft,a ratchet engaging pawl on said lever, means to oscillate the liftinglever to raise the platform, pawl and ratchet means to retain theplatform in elevated position, and means to release the pawls of thelifting means and the retaining means to allow the platform to lower,said means comprising a foot treadle mounted on the supporting frame, amember journaled on said shaft and having a pawl stripper pivotedthereto in operative relation with the pawl of the lifting means, meansincluding d@25 a link connecting said foot treadle and said pawlstripper, means including a second link connected with the first link torelease the pawl of the retaining means whenever the foot treadle isoperated to actuate the pawl stripper, and a link brace .30 connected tothe frame and to the member for rigidly connecting the member to theframe.

8. A lift truck comprising the combination of a wheel supported mainframe, a lifting frame carried thereon, a steering handle mounted on 335one of the frames, lifting means adapted to elevate said lifting framerelative to the main frame and actuated by the steering handle,including pawl and ratchet mechanism and laterally movable links toconnect the mechanism to the steer- M@ ing handle, and means to hold thelifting frame in any of its elevated positions, said means comprising arotatable ratchet on the main frame and means to rotate the ratchet inaccordance with the elevation of the lifting means, said last M5 namedmeans being actuated by the lifting means.

9. A lift truck comprising, in combination, main and lifting frames,lifting means `comprising pawl and ratchet mechanism for elevating thelifting frame and including a vertically oscil- 150 latable liftinglever having a pawl, a handle pivoted to one of the frames for steeringthe truck and for actuating the lifting cans, and meansl including alink connected to the lifting lever for 1both lateral and fore and aftswinging for actuating the lifting means from the handle.

10. A lift truck comprising, in combination, wheeled supporting means, alifting frame, pawl and ratchet mechanism for elevating the liftingframe relative to said supporting means and including a pair ofvertically swinging lifting levers, a pin connecting the outer ends ofsaid lifting levers, a link journaled on the pin and capable of limitedlateral swinging relative thereto, a steering handlemounted on thewheeled supporting means for both lateral and vertical swinging, andmeans connecting the handle with said link. 11A lift truck comprisingthe combination of a main frame, a lifting frame, means for raising thelifting frame, and means for retaining the lifting frame in elevatedposition including a pawl and ratchet mechanism, a shaft driven from thelifting means, and a bearing on the main frame for one end of the shaftcomprising relatively stationary and movable members allowing bothpivotal and rotational movement of the shaft.

12. A lift truck comprising the combination of a main frame, a liftingframe, means for raising ,30,

the lifting frame, and means for retaining the lifting frame in elevatedposition including a pawl and ratchet mechanism, a shaft, a bearingcomprising a spherical race mounted on the shaft, a

bearing mounting on the main frame, a race carried on the mounting, andantifriction rollers cooperating with the races, said races and rollersbeing formed to allow swinging movement of the shaft, and a thrustbearing cooperating with said first named bearing.

13. In a lift truck having wheeled supporting means, a lifting frame,and means to elevate the lifting frame relative to the wheeledsupporting means, means to cushion the return of the lifting frame tolowered position comprising a uid `45,

cylinder and piston, and an auxiliary chamber in communication with saidcylinder.

14. In a lift truck having a main frame, a

lifting frame, and means to elevate the liftingV frame relative to themain frame, means to cushion the return of the lifting frame to loweredposition comprising a fluid cylinder pivotally connected with theelevating means, a piston in said cylinder, a piston rod movable in thecylinder, means including a swingable roller bearing connecting thepiston rod with the main frame, andplatform retaining means connectedwith the piston rod. Y

l5. In a lift truck having a main frame, a lifting frame, and means toelevate the lifting frame relative to the main frame, means to cushionthe return of the lifting frame to lowered position comprising a fluidcylinder pivotally connected with the elevating means, a piston in saidcylinder7 apiston rod connected to the piston and to the main frame, anda roller bearing assembly supporting the rear end of the piston rod onthe main frame, said cylinder being adapted to move outwardly of thepiston rod when the platform is raised.

16. In a lift truck having Wheeled supporting means, a lifting frame,and means to elevate the lifting frame relative to the wheeledsupporting means, means to cushion the return of the lifting frame tolowered position comprising a uid cylinder, a piston and piston rodslidable within the cylinder and connected with the supporting means,liquid within the cylinder on both sides of the piston, said pistonhaving a restricted opening therethrough so that the movement of thepiston toward the closed end is opposed, and an auxiliary chamberconnected with the other end of the cylinder and adapted to supplyliquid to said cylinder.

17. A lift truck comprising the combination of wheeled supporting means,a platform elevatable with respect thereto, means for lifting theplatform comprising a ratchet journaled on said wheeled supportingmeans, means connecting the ratchet with the platform, a lifting leverhaving pawl means to actuate the ratchet, a manually operated lever, andmeans comprising a series of links having limited lateral movement andadapted to operatively connect the two levers.

18. A lift truck comprising a supporting frame, a platform elevatablewith respect thereto, means for lifting the platform comprising a shaftjournaled on the supporting frame, a ratchet secured thereto, a manuallyoperated lifting handle including a U-shaped lifting lever, a secondlifting lever mounted on said shaft and having pawl means to actuate theratchet, and a single link means connecting said two lifting levers.

19. A lift truck comprising wheeled supporting means, a platformelevatable with respect thereto, and means for lifting the platform.comprising a lifting handle movable about a vertical axis, a forwardlyand upwardly extending link having its upper end connected with thehandle and movable vertically thereby in line with said axis, and meanspivotally connecting the lower end of said link with the platform.

20. A lift truck comprising the combination of a main frame, a liftingframe mounted on the main frame to swing forwardly and upwardly,supporting and steering wheels for the main frame, a king bolt journaledin the main frame and on which the steering wheels are mounted, alifting lever connected to the upper end of the king bolt and pivoted toswing vertically, a downwardly and rearwardly extending link having itsi upper end carried on said lifting lever and movable therebysubstantially vertically in the pivotal axis'of the king bolt, and meansoperatively connecting the lower end of said link with said platform.

21. A lift truck comprising the combination of a supporting frame, aplatform elevatable with respect thereto, means for lifting the platformcomprising a shaft journaled on the supporting frame, a ratchet securedthereto, a manually operated lever, a lifting lever mounted on saidshaft and having pawl means to actuate the ratchet, and means connectingsaid levers including a link having its forward end movablesubstantially vertically by said manually operated lever and its lowerend connected with said lifting lever to swing arcuately therewith.

22. A lift truck comprising a supporting frame and a lifting platform, aplurality of swinging links supporting the platform on the frame, a

steering lever for the truck, a shaft journaled on the frame, cranks onthe shaft directly connected with the outer ends thereof, linksconnecting the cranks with the platform, and means to rotate the shaftincluding a ratchet secured to the shaft,

a lifting lever journaled to turn about the shaft, a ratchet engagingpawl on said lever, a link connected to said steering lever and saidlifting lever, whereby operation of said steering lever causes said pawlto engage the ratchet and turn icc said shaft, and means for holding thelifting platform at any one of a plurality of positions intermediate theengagement of said pawl with successive teeth on said ratchet.

23. A lift truck comprising a supporting means, platform elevatable withrespect thereto, mechanism for lifting the platform, a manually operatedlifting handle swingable about a vertical axis and including a liftinglever having a curved portion, and a single link means connecting thecurved portion of said lifting lever with said mechanism, said curvedportion being formed so that said link means moves substantiallyvertically along said axis.

24. A lift truck comprising the combination of a main frame, a liftingframe mounted on the main frame to swing forwardly and upwardly,supporting and steering wheels for the main frame, a king bolt journaledin the main frame and on which the steering wheels are mounted, amanually operated liftinglhandle including a U-shaped lifting leverconnected to the upper end of the king bolt and pivoted to swingvertically, a lifting link connected at its forward end with saidU-shaped lifting lever, said forward end being moved vertically therebyin line with the axis of the king bolt, and means connected with theother end of the lifting link for raising the lifting frame.

ARTHUR M. BARRETT.

CERTIFICATE OF CORRECTIN.

Patent No. 1,954,980. April 17, 1934,

ARTHUR M. BARRETT.

1t is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 5,line 145, claim 8, for "means" read frame; and that the said LettersFatent should be read with this correction therein that the same mayconform to the record of the ense in the Patent Office.

Signed and sealed this 19th day of june, A. D. 1934.

Bryan M. Battey (Seal) Acting Commissioner of Patentse

